Nonsyndromic Cleft Lip or Cleft Palate. Previous studies have shown an association of the transforming growth factor-alpha (TGFA) locus with non-syndromic cleft lip with or without cleft palate. To further characterize this association, we have continued to look for mutations in the gene. We have identified four polymorphisms that are in the 3' untranslated region of the mRNA. One of the polymorphisms was found to be in a weak association with non-syndromic cleft lip with or without cleft palate. The same polymorphism was found to be in association with nonsyndromic, isolated cleft palate. Currently, experiments are being performed to determine if the associated allele is transcribed at the same level as the other alleles. In addition, we are undertaking efforts to expand our search for mutations by sequencing further into the promotor and also all of the exon/intron boundaries. This will allow for mutation detection in our population of patients using our current techniques of SSCP and DGGE.